Music arrangements

I'm planning on composing my own music for games and stuff. I'm buying a small MIDI keyboard to get some practice, but I really have no idea on what role does every instrument have when composing a soundtrack.

Does anyone know a good book about music composition or some other way to get started?

As for my music skills, I know a bit about electric keyboard and guitar, that's all.

there isn't any books afik
It is mostly style dependent trance for ex uses 4/4 rythm with 2 or three base notes, dnb uses the amen break as a template, techno is usally only drums with monophonic sequences.
any other syles in eletonic music are usally derived from that.

if you want to create something innovative you might try this out:
http://bowerbird-studios.com/aicaramba/page2.html

If you are into band music there is probably much more but idk how2 do that.

There are a lot of books of harmony, scales, orchestration, and you will learn a lot by listening to different styles of music, but the final master is the experience of composing.

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